Filter cleaning system and filter cleaning method

A filter cleaning system (1, 1A) according to the present disclosure is provided with a reservoir (2), an infusion path (3, 3A), a circulation path (4), a first supply unit (5), and a second supply unit (6). The storage unit stores a liquid to be passed to the filter (100). The liquid conveying path conveys the liquid stored in the storage part to the filter. The circulation path returns the liquid output from the filter to the storage part. The first supply unit supplies a first liquid to the storage unit. The second supply unit supplies a second liquid having a lower surface tension than the first liquid and having an affinity with the first liquid to the storage unit. 本公开的过滤器清洗系统(1、1A)具备贮存部(2)、输液路(3、3A)、循环路(4)、第一供给部(5)以及第二供给部(6)。贮存部贮存要向过滤器(100)通液的液体。输液路向所述过滤器输送贮存于贮存部的液体。循环路使从过滤器输出的液体回到贮存部。第一供给部向贮存部供给第一液体。第二供给部向贮存部供给表面张力比第一液体的表面张力小且具有与第一液体的亲和性的第二液体。